Is it okay to use a standard Rx switch harness as the on/off switch for the electronic ignition of my gas engine. The battery will be a 4.8v 700mAh Nicad.

probably not, it is questionable if it will stand the vibration. I use a aircraft instrument system toggle switch.

On electronic ignition it will work fine as most electronic ignitions are set up that way. If it would not hold up to vibration, it would be useless for the radio as well. I use a radio switch harness on all my C&H equipped motors and never had a problem. Just remember that on electronic ignition, you supply battery power to run, not ground the coil to kill. (continuity to run, open to kill)

You battery seems small... what motor?

I use SuperRocker switches... they are rated to 16 Amps, have dual self cleaning contacts, 22 gauge wire, are designed for full-scale aircraft, and have a lifetime warranty.

If it's one of mine a 700 ma battery will run the ignition for 3 1/2 hours....How long do you want to fly ?
Average current draw is less than 200 ma at ANY rpm
A standard receiver swithch works just fine

Thanks for the information, and yes Ralph, it is for one of yours.

I am just getting everything together in readyness for when my G23 comes back from you doing your magic on it.